Inium chloride



Usines-fermes @maar @Friend HAMILTON YoU,Nc"'cAs TNnIyor LONDON, ENGLAND..

Paocesj-s OF'. eue-iframes aan iva i N a u la en Loan ne@` srncirrcarron reigning 'pai-abr vnfealms raient no. 422,500, dated ,March 4,1890.

' `1 Apprends nanofentaeaisss. seran no. 331.591. naman.)

To a/lfzohm it may concern# i j .i

Be it lgnown that I, HAMILTON YOUNG CAST- f una, a citizen of the United Statesof America,

' and usef ul ImprovedProcess' of Purifying the ,residing at 115 Cannon Street, in the city o f. London, England, have invented a certain new Anhydrous Double-Chloride Compounds of Aluminium; and I dohereby declare that the.

v following is afull, clear, and exact descrip`V tion of the in ventiomwhiehwill enable others skilled in. the art tojwhich it ap'pertains to make and usethe'same.

4 The object of thi-s invention is to purify the 'anhydrous double chloride compoundsv of'. aluminium. 1

Although' reference is only made herein to .the double chloride of aluminium and sodium, it Will be evident that the process is equally `applicable tov 'other double chloride comzopounds of aluminium-#such for instance, as

- thedoublechloride of aluminium 'and potas` sium.v I In the production of metallic aluminium kfrom the double chloride (by the action of sodium or otherwise) it is of great importance that this compound should be pure.

The double chloride of aluminium and sodium is now generally manufactured by passing chlorine gas over or through a highly- .'heated mixture of alumina carbon and salt -contained in fire-clay retorts,the double chloride .formed by reaction being distilled and condensed in receivers attached tothesaid .retorts through which the vapors are made 4to pass. In manufacturing the double chloride in'this manner it becomes much contaminatedwith ferrous and ferrie chloride, 'produced by the action of the chlorine gas and carbon monoxide upon the iron contained -in the materials composing the charge, and also contained in the fire-clay of which the retorts areA composed. In thev subsequent treatment of this impure double. chlo- .ride with sodium for the production of aluminium both thc chlorides of aluminium and iron are reduced to the metallic state, yieldingan aluminium of inferior qual-ity, due to the presence of iron, the proportion of the same in the aluminium produced depending uponV the quantity o f jiron 'contained vin the ern-de chloride employed.

'- Mypresent invention relates toa; method by the use of an electric current, the apparaitus beingso arranged and the-quantitybf Y current being so regulated and applied in` such a manner as will only-decompose the ferrous and ferrie chlorides,^causing metallic iron to be deposited and leaving the double chloride'of aluminium and sodium pure."

I In order that my invention may be clearly understood, I take the following as an exam- -ple of hovv my invention may be practically ampres with which to carry out' t he puriti- 4 cation. One thousand ampres of current passed into mol-ten crude chloride will decompose and precipitate about seven hundred grams of iron per hour from the equivalent amount of ferrie chloride, Which is about the amount of iron contained in three hundred and ten pounds of crude chloride@ containing .5 (onedialf of one) per. eent.'of

iron.

My experiments have 'proven that if the one thousandl ampres were continuously passed through the crude double chloride in a single bath and no means were taken to keep the electrolyte in motion there would be a greateror less deposit of metallic aluminium with and among the iron deposited on the negative electrodes, and to prevent this and to accomplish the separation with little or no Waste of either material or current I propose to purify the crudev chloride gradually by treating it while in motion in a series of baths to a series of electric currents of decreasing quantity. A convenient arrangement of ap-- paratus for this purpose is indicated inthe accompanying drawings, in which- Figure l. is a View in section. 'Fig 2 1s a perspective'view of one of the inetalvplates v used as a negative electrode alternately inthe decomposing-cells With theplate, as shown i in Fig. 3, also as a negative electrode.

The vessel A serves for .melting the crude 'chloride (being yset in brieli-ivork over a small" fireplace) and is provided-With a tap Bbyl means of which the quantity of noltcnchlo- ,of purifying the anhydrous double .chlorides 'pride flowing; into tank Ccanlbe regulated-.1

Tank C -is a long narrow Airon sessel (preferably porcelain-lined) fitted with a series of electrodes so larranged that the molten chloride will flow in a regular mannerbetween the plates forming these' electrodes. u This end may be attained fby arranging the plates as follows: The anodes E (which are preferably of carbon) are of such a size that when fixed in place they do not either extend to the bottom or sides of the bath. The cathodes II (which are of metal, preferably of sheet-alu 'minium, about one-sixteenth inch or oneeighth inch thick) are of the shape shown in Figs..2 and 3. These plates are of thc same Width as the bath, and when placed in position between the carbon anodes cause the chloride flowing from A to take-the direction shown by the arrows. The tan-ks C2 and C3 are similarly fitted, and are each provided with overflow or discharge pipes F, thc last named discharging into'the receptacle D for the purified material.' yThe vessel A and tanks C', C2, and C3 are sutlieiently hea-ted to keep the chloride just melted, so that it may run freely. The anodcs and-cathodes in each bath are so connected with the poles of the dynamo that thcone thousand am pres of current used are` divided, so that, say, about six hundred pass through the moving elec- 'trolyte intank C per hour, three hundred through' that in C2 per hour, and one hundred through that in C3 per hour. If, therefore, the tap B is set so that the three hundred and ten pounds of impure chloride are passed Jfrom vessel A to tank (Y per hour and there submitted to a current of six hundred ampres, four hundred and twenty grams of iron out of the seven hundred contained therein will be deposited on the cathode's, together with a quantity of salt (NaCl) from the double chloride. In passing through the tank C2 the partially-purified chloride is submitted to a furthercurrent of three hundred ampres, a further' quantity of two hundred and teu grams ofv iron being inflike manner deposited, while in `fiowing through tank C the remaining seventy grams will be eliminated bythe one hundred ampres of current, and the mat erial flowing into receptacle D will be found to be practically pure. If, therefore, the vessel A be kept dulycharged with the impure chlocation will be obtained, it being only necessary to remove the Vcathodes from time to time and substitute clean ones, while those removed are cleansed from the adheringiron' andsalt together with a little double chloride and with a very small amount of metallic aluminium, which has been deposited owing to a small proportion of the double chloride of aluminium and sodium having been decomposed.

The anodes, if made of carbon, are ofcourse gradually disintegrated by the chlorine, and

require to be removed from time to time and new ones substituted.

I do not, of course, confine my process to the treatment of double chlorides containing .5 (one-half of one)` per cent. of iron, or to acurrent of 'one `thousand ampres, as these quantities have simply been' assumed for the purpose of illustration; nor do I confine myself to the particular form or number of baths, as the operation might be conducted in a singie bath if due care were taken to diminish the current at successive stages of the operation in the' manner indicated herein, the molten crude or partially -purified double chloride being kept in motion throughout the operation. v

I am aware that iron has heretofore been separat-ed from'its solutions by electrolysis, and suchprocess I do not claim, broadly.

- Having now particularly described and ascertained thc nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. The process of purifying thc anhydrous doublechloride compounds of aluminium containing iron, which consists in removing said iron from such compounds when in motion and in a fused conditionby electrolysis;

substantially as set forth.

2. The process of purifying the anhydrous doublechloride compounds of aluminium containing iron, which consists in first melting the crude material and then causing it to pass through a series of receptacles in which it is subjected while in motion to the 'action of electric currents, substantially as set forth, by which .the iron chlorides are decomposed and the metallic iron deposited.

The process of purifying the anhydrous double-chloride compounds of aluminium containing iron, which consists in treating the crude material'when in lnotion and in a fused condition to an electric current of gradually-decreasin g quantity proportioned to the gradually-decreasing quantity of iron con tained inl the material, substantially as and for the purpose set forth.l

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

HAMILTON YOUNG CASTNER.

Witnesses:

ALLEN l. JoNEs, H oRArro A. LEE.

ITO 

